I'd like to see the ability to ping the phone via SMS and have the coordinates returned for current position. Doing this (vis SMS) direct to the unit would be ideal, but it could be bounced off the server as well. This would be excellent for mobile tracking in areas where 3G coverage is unavailable or poor signal strength is being experienced. It seems low-tech on the face, but once you work with coordinates awhile, you can ballpark the location.